A display refers to a device that expresses visual information, for example, images or videos. A recent display has evolved from a level expressing images or videos two-dimensionally to a level expressing visual information three-dimensionally for allowing depth perception or stereovision. A display provided with an electric signal as input information can be referred to as an “electronic display”.
There are types of electronic displays: a Liquid Crystal Display (LCD), a Light-Emitting Diode (LED), an Organic LED (OLED), and electronic paper. Among these types of electronic displays, an LCD and an OLED are often used.
For example, in an LCD, a plurality of liquid crystal pixels can be arranged in a matrix form on a substrate, and two transparent electrodes can be connected to each of the liquid crystal pixels. Polarizing filters can be arranged at both sides of each liquid crystal pixel such that their polarization axes are perpendicular to each other. In a normal state, the specific arrangement of the liquid crystal pixels can pass light through the polarizing filters, but if voltage is applied to the transparent electrodes of each liquid crystal pixel, the arrangement of the liquid crystal pixels can be fixed to block light without passing light.
An electronic display of a type different from that of an LCD can be, for example, an OLED. The OLED can produce light in LEDs by using an organic compound. Thus, in the OLED, the expression range of light can be wider than that of the LCD. The OLED can express a color using a scheme, for example, a three-color scheme, a conversion scheme, or a color filter scheme. The three-color scheme can implement various colors by using light-emitting layers having different colors of red, green, and blue. In the three-color scheme, the purity of a color can be improved using a color filter to be described below. The conversion scheme can implement a color such as red or green by passing at least a part of light produced, for example, in a light-emitting layer of blue, through a color conversion layer. The color filter scheme can implement a color corresponding to each color filter by passing at least a part of light produced, for example, in a light-emitting layer of white, through color filters of various colors such as red, green, or blue.
Various types of displays, as well as the foregoing LCD and OLED, can be applied to electronic devices.
In a process of manufacturing a display or using a display by a user, various types of defective pixels can be generated. Defective pixels can be a hot pixel that is turned on at all times, a dead pixel that is turned off at all times, and a stuck pixel that can be turned on or off, regardless of an input signal for the pixel.
In the manufacturing process of the display, a display panel can be produced and released to the market after removing a defective pixel therefrom, according to the internal standard of a display manufacturer. Therefore, a defective pixel generated in a display panel during the manufacturing process can directly affect the yield and profit of the display manufacturer.
During the user's using process, defective pixels can be generated for various reasons, such as performance deterioration due to use, pressure, shocks, and so forth. The defective pixels generated during the using process can degrade user's satisfaction with product quality. Replacement or disposal of a display panel in which a defective pixel is found can increase the cost of post management of the manufacturer. Moreover, along with the tendency of display development toward high resolution and large size, the possibility of a defective pixel in the display panel can increase further.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.